On The Tyra Banks Show, Spencer Pratt says that he is "100%" sure there was a rumored sex tape starring Lauren Conrad, US reports.

Spencer Pratt "100%" sure Lauren Conrad sex tape exist

"I know for 100% fact it did exist – 1000%!" he declares.

Banks asks if Pratt had actually seen it.

"I would never watch that!" Pratt says. "I would rather throw up... but I know for a fact, and I would take a lie detector test."

Heidi Montag — who appeared alongside Pratt on the show — also claims the tape was "not a rumor. From what I have heard from confirmed sources... her ex-boyfriend was going around trying to sell it."

Banks then asks Montag, if she hadn't seen the tape, how could she be so sure it existed.

"Well, I mean, I am not sure she has it anymore... but from what I've heard..."

Montag adds, "I am not really allowed to elaborate."

Image WENN